Instana context loss

Problem

When the @instana/collector is loaded into a Node.js application, but that application also uses cls-hooked to propagate and preserve it's own context, then they both seem to conflict and only one context is propagated, furthermore upon closer inspection, this problem only seems to happen when:

• The request contains a payload
• The request object is explicitly bound through the use of bindEmitter

Reproduction

A reproduction code is included. Use node or docker to execute it while the instana agent is running.

Running directly on the host

$ node server.js

Running as a docker container

docker build -t test-instana .
docker run --network=host --pid=host --name "test-instana" --rm -ti test-instana:latest node server.js

Test cases

GET request

curl -X GET http://127.0.0.1:3000 | jq

{
  "body": {},
  "instana": "e4b87d663e102644",
  "local": "055523c3-ec33-4081-8dfb-001e9367f901"
}

POST request with payload (json)

curl -X POST http://127.0.0.1:3000 -d '{ "key": "value" }' -H "Content-Type: application/json" | jq

{
  "body": {
    "key": "value"
  },
  "instana": "unknown",
  "local": "6ec05320-bf33-477c-a897-2d95d87b54a7"
}

POST request without payload (json)

curl -X POST http://127.0.0.1:3000 -H "Content-Type: application/json" | jq

{
  "body": {},
  "instana": "9aa7ad40adbc00ab",
  "local": "d45eea85-1a09-45b0-9727-a3cb433b8a5d"
}

POST request with payload (form)

curl -X POST http://127.0.0.1:3000 -d 'key=value' -H "Content-Type: application/x-www-form-urlencoded" | jq

{
  "body": {
    "key": "value"
  },
  "instana": "unknown",
  "local": "a862b3f3-c46f-42fd-a5a8-06e89d9febe0"
}

POST request without payload (form)

curl -X POST http://127.0.0.1:3000 -H "Content-Type: application/x-www-form-urlencoded" | jq

{
  "body": {},
  "instana": "a02de9971d2f0bc2",
  "local": "e31d99fa-d19b-464b-8549-5d5929e9d368"
}

Notes

• The samples above are meant to demostrate that the Instana instrumentation breaks under this conditions. When this happens on our production systems, only self time is recorded and no additional services appear on traces.
• If binding of the request event emitter is removed, then the instana traces work again but the local context is lost